I am about to have the Airdog 100 installed and have a quick and easy questions. Someone said to put the bigger spring in for 17psi versus the regular 15psi and i twas included in his parts for the AD. There is one spring in the bag with hardware, is the 15psi spring in already and you have to change it with this one or it's an extra and I need to get it here before I do the AD install? Just curious, wasn't positive. Thanks!

It seems the posts I have read about the AD that it comes with the low pressure spring installed. From what i have read everyone seems to be swapping springs to increas the pressure. You could call the vendor you bought it from or AD and ask to be safe. My ADII has a regulator so I dont have to mess with springs.

I would bump it up, from what Mike has been teaching you want to be above 14 all the time.

the ad come,s with the smaller spring allready installed the one in the kit is the bigger spring for the higher peresser

the ad come,s with the smaller spring allready installed the one in the kit is the bigger spring for the higher peresser

Sweet! Thats what I was looking for. I am going to call the vendor too to make sure it's not opposite but I am glad I don't have to try to explain that I needed the higher pressure spring. You would think if everyone knows the pressure should be 15psi at WOT at a minimum these companies would more adjust their equipment so it's hook it up and go and not have to worry about some of this stuff. Thanks all of you for your input! I appreciate it!

I know that it was marked on my airdog when I got it. Right on the tag. It said it was set to 15 psi + or - 1psi. I pulled the return line fitting off and put in the other spring that was sent with the pump.

i am sure of what spring is in the ad and what comes in the kit seeing i am a dealer for both ad and fass systems

i am sure of what spring is in the ad and what comes in the kit seeing i am a dealer for both ad and fass systems

Haha. That's good to know, so you do actually know for sure! Probably a dumb question, but why would they put the smaller spring in and send a 17psi with? or why not just install it with the 17 and not send a different one at all? Thanks for the info!

the ad in reality come,s with a 17pd spring and the one in the box is a 20pdi think its more of a customer thing why they do it no real reason to i can see some fella,s want that high psi and do not know that the vp44,s are not happy with too much psi

You want to fall in the 14-20 PSI pressure range while driving. Like my truck I've got about 19 PSI at idle and 17 PSI at WOT. This is a good pressure span and pressure fall.

I know the minimum specification is 10 PSI but you have to remember Bosch requires 70% of the fuel to be returned back to the tank for proper cooling and lubing requirements. But if the overflow valve is closed by 10 PSI and open by 14 PSI that mean you've got to keep above 14 PSI to keep the return flow going.

Keep it in the green!

You want to fall in the 14-20 PSI pressure range while driving. Like my truck I've got about 19 PSI at idle and 17 PSI at WOT. This is a good pressure span and pressure fall.

I know the minimum specification is 10 PSI but you have to remember Bosch requires 70% of the fuel to be returned back to the tank for proper cooling and lubing requirements. But if the overflow valve is closed by 10 PSI and open by 14 PSI that mean you've got to keep above 14 PSI to keep the return flow going.

Keep it in the green!

I called the company about my Airdog 100 and they said 15psi in the pump and 17psi spring is in the bag. So my next question is if you don't want to be below 15 what can you do if it is dropping to 13 or 14 if the Airdog is installed? I obviously don't drive WOT but just wondering if at highway speed if it's below 15. Thank you!

With the 15psi spring that came with the pump it ended up being 17psi at idol and 15 at wot on my pump when I installed it. I put the 17psi springIn because it put me at 19psi at idol and 17psi at wot, which I prefer. Try installing the pump and take it for a drive. If your not happy you can put the 17psi spring in and you should be good.